Railroad car bearing adapter pad

ABSTRACT

A railroad car bearing adapter pad including a wear resistant body formed with one or more compressible resilient conductive plugs which provide electrical conductivity or continuity between a side frame and a bearing adapter and thus between the railroad car body and the railroad tracks when the bearing adapter pad is mounted on a bearing adapter in a pedestal jaw opening of a side frame.

BACKGROUND

Most conventional freight railroad cars include a car body and twospaced apart trucks. The car body or car body underframe includes twospaced apart center plates which respectively rest on and are rotatablyor swivelly received by bolster bowls of the two trucks. The trucksrollingly support the car body along railroad tracks. Each truckincludes two side frames and a bolster which supports the bolster bowlof that truck and which extends laterally between and is supported bythe two spaced apart side frames. Each side frame defines a centeropening and pedestal jaw openings on each side of the center opening.Each end of each bolster is supported by a spring group positioned inthe center opening of the side frame and supported by the lower portionof the side frame which defines the center opening. Each truck alsoincludes two axles which support the side frames, and four wheels andfour roller bearing assemblies respectively mounted on the ends of theaxles. The truck further includes four bearing adapters respectivelypositioned on each roller bearing assembly in the respective pedestaljaw opening and four bearing adapter pads respectively positioned oneach bearing adapter. Each bearing adapter pad: (a) reduces the wear ofthe bearing adapter and the pedestal roof (i.e., the wall of the sideframe which defines the top of the pedestal jaw opening) by reducingmetal to metal contact between these components; and (b) decouples theaxle and the wheels from the side frame to improve steering of thetruck.

U.S. Pat. No. 7,387,074 discloses a bearing adapter and bearing adapterpad. The bearing adapter is configured to fit on top of the bearingassembly and the bearing adapter pad is configured to fit on top of thebearing adapter. The bearing adapter pad includes a body and four legswhich respectively extend downwardly from opposite longitudinal edges ofthe body. The legs are spaced laterally at each longitudinal edge of thebody such that the legs are received in openings between the laterallyspaced shoulders of the bearing adapter. This bearing adapter pad ismade from an elastomer such as polyurethane and is being commerciallysold by Amsted Rail.

One problem with this elastomer bearing adapter pad is that it isnon-conductive and thus is unable to provide electrical continuity orconductivity between the side frame and the bearing adapter (and thusbetween the car body and the tracks). Such electrical continuity orconductivity is needed to provide a ground for the car body whicheliminates or reduces the buildup of static electricity on the car body.Such electrical continuity or conductivity is also needed to provide theability for the car body or components thereof (such as electricsolenoids for doors on bottom dump freight railroad cars) to obtainelectrical power or electrical signals from the railroad tracks orrails. In other words, this electric continuity or conductivity isneeded to provide electric power or electric signals transmitted fromthe tracks to one or more components of the car body. Such electricalcontinuity or conductivity is further needed to provide electricalcontinuity or conductivity between railroad cars to trigger railroadcrossing signals.

Accordingly, Amsted Rail has manufactured this elastomer bearing adapterpad with copper plugs which extend through the body of the bearingadapter pad and which provide metal to metal conductive contact and thuselectrical conductivity or electrical continuity between the pedestalroof and the bearing adapter. However, over time, these copper plugstend to break off or wear down or off and then become less effective andpossibly not effective at all in providing electrical continuity orconductivity between the side frame and the bearing adapter (and thusbetween the car body and the tracks).

Accordingly, there is a need to solve this problem.

SUMMARY

The present disclosure provides a railroad car bearing adapter pad whichsolves the above problem. The railroad car bearing adapter pad ofvarious embodiments of the present disclosure generally includes a bodyhaving one or more compressible resilient wear resistant conductiveplugs which provide electrical conductivity and continuity between theside frame and the bearing adapter (and thus between the car body andthe tracks). The bearing adapter pad of the present disclosure overcomesthe above problem by providing a railroad car bearing adapter pad whichensures better electrical conductivity and continuity than known bearingadapter pads.

More specifically, the bearing adapter pad of various embodiments of thepresent disclosure includes one or a plurality of spaced apartcompressible resilient wear resistant conductive plugs positioned in thetop section of the body of the bearing adapter pad. Each of theconductive plugs transversely extends slightly above and slightly belowthe planes of the top and bottom surfaces, respectively, of the topsection of the body of the bearing adapter pad to facilitate theelectric conductivity or continuity between the side frame and thebearing adapter (and thus between the car body and the tracks throughthe center plate, the bolster bowl, the bolster bowl liner, the bolster,the side frame, the bearing adapter pad, the bearing adapter, thebearing assembly, the axle, and the wheel). In various embodiments, theconductive plugs are each made from a resilient material which enablesthem to continue to provide electric conductivity and continuity evenwhen they are compressed or deformed. In various embodiments, theconductive plugs are also wear resistant.

Other objects, features, and advantages of the present disclosure willbe apparent from the following detailed disclosure, taken in conjunctionwith the accompanying sheets of drawings, wherein like referencenumerals refer to like parts.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a side view of a conventional freight railroad car.

FIG. 2 is a fragmentary exploded perspective view of a bolster bowl, abolster, a side frame, and a bearing adapter of a freight railroad cartruck, and a bearing adapter pad of one embodiment of the presentdisclosure, and which includes four resilient conductive plugs.

FIG. 3 is an enlarged top perspective view of the bearing adapter pad ofFIG. 2.

FIG. 4 is an enlarged bottom perspective view of the bearing adapter padof FIG. 2.

FIG. 5 is a fragmentary cross sectional view of the bearing adapter padof FIG. 2 and one of the conductive plugs, taken substantially alongline 5-5 of FIG. 3.

FIG. 6 is a top perspective view of one of the conductive plugs of thebearing adapter pad of FIG. 2.

FIG. 7 is a top plan view of the conductive plug of FIG. 6.

FIG. 8 is a side elevation view of the conductive plug of FIG. 6.

FIG. 9 is a cross-sectional view of the conductive plug of FIG. 6 takensubstantially along line 9-9 of FIG. 8.

DETAILED DESCRIPTION

Referring now to the drawings and particularly to FIGS. 1, 2, 3, 4, and5, one embodiment of the bearing adapter pad of the present disclosurewhich is generally indicated by numeral 100 is shown with respect to afreight railroad car 10 and specifically with respect to a truck 12 of afreight railroad car 10. In this example illustration, the truck 12includes a bolster 14 (shown in fragmentary in FIG. 2), a bolster bowl16 (shown in fragmentary in FIG. 2) on the bolster 14, a side frame 18(shown in fragmentary in FIG. 2), and a bearing adapter 50 configured tobe positioned on a bearing assembly (not shown) which in turn ispositioned on an axle (not shown).

More specifically, in this example illustration, the side frame 18includes two downwardly extending pedestal jaws including a firstpedestal jaw 22 and a second pedestal jaw (not shown) on the oppositeside of the center opening 24 of the side frame 18. The pedestal jaw 22includes an inside wall 26, a top wall or pedestal roof 28, and anoutside wall 30 which generally define the pedestal jaw opening 33. Thepedestal jaw 22 also includes an inner thrust lug 30 (not shown in FIG.2) at the intersection of the inside wall 26 and the top wall 28, and anouter thrust lug 32 (partially shown in FIG. 2) at the intersection ofthe outside wall 30 and the top wall or pedestal roof 28. It should beappreciated that the bearing adapter pad of the present disclosure canbe implemented with differently configured side frames and pedestaljaws.

In this example illustration, the bearing adapter 50 generally includesa body 52, a plurality of legs 54, 56, 58, and 60 (not shown) extendingdownwardly from the body 52, and a plurality of raised edge supports 64,66, 68, and 70 extending upwardly from the body 52. The body 52 of thebearing adapter 50 includes a substantially rectangular top section 72which has a substantially flat top surface. The top section 72 and theraised edge supports 64, 66, 68, and 70 form a receiving surface andpocket for bearing adapter pad 100. The body 52 and the legs 54, 56, 58,and 60 (not shown) of the bearing adapter 50 include lower walls thatdefine an arcuate opening 82 configured to receive or sit on the bearingassembly (not shown). In this example illustration, the bearing adapter50 is a unitary cast steel structure, although it can be formed in othermanners. It should be appreciated that the bearing adapter pad of thepresent disclosure can be implemented with differently configuredbearing adapters.

In this illustrated embodiment, the bearing adapter pad 100 (as bestseen in FIGS. 3 and 4) generally includes a body 102 and a plurality oflegs 104, 106, 108, and 110 extending from the body 102. The body 102 ofthe bearing adapter pad 50 includes a substantially rectangular topsection 112 which has a substantially flat top surface. The body 102 andthe legs 104 and 106 form a first thrust lug opening 114. The body 102and the legs 108 and 110 form a second thrust lug opening 116. When thebearing adapter pad 100 is positioned on top of bearing adapter 50, thelegs 104 and 106 are supported laterally against depending shoulders ofbearing adapter 50. When the bearing adapter pad 100 is positioned ontop of bearing adapter 50, the legs 108 and 110 are supported laterallyagainst depending shoulders of bearing adapter 50.

As further illustrated in FIGS. 6, 7, 8, and 9, in this exampleembodiment, the bearing adapter pad 100 and specifically the body 102includes a plurality of conductive resilient plugs 130, 132, 134, and136 integrally mounted in and slightly extending transversely from(i.e., above and below) opposite sides or surfaces (i.e., the top andbottom surfaces) of the top section 112. In this illustrated embodiment,each conductive plug 130, 132, 134, and 136 is identical; however, itshould be appreciated that the present disclosure contemplates that theconductive plugs do not have to be identical, and that two or more ofthe conductive plugs may be different. It should also be appreciatedthat the present disclosure contemplates that more than four conductiveplugs can be employed in that bearing adapter pad and that less thanfour (and at least one) conductive plugs may be employed in the bearingadapter pad of the present disclosure. The present disclosure furthercontemplates that the conductive plugs may be of different sizes. Thepresent disclosure further contemplates that the conductive plugs may beof different materials. It should also be appreciated that theconductive plugs are not limited to being cylindrical and can be inanother suitable shapes in accordance with the present disclosure.

Since each conductive plug 130, 132, 134, and 136 is identical in thisillustrated example, conductive plug 130 is used as an example tofurther describe the conductive plugs. In this example embodiment,conductive plug 130 generally includes a central portion 140 and top andbottom engagers 142 and 144 which transversely extend from opposingsides of the central portion 140, and which are configured to engage thetop wall 28 of the side frame 18 that defines the pedestal jaw opening32 and the top surface of the top section 72 of the body 52 of thebearing adapter 50. More specifically, the plug 130 has a thickness(i.e., height) which is greater than the thickness (i.e., height) of thetop section 112 of the bearing adapter pad 100. When the conductive plugis positioned centrally in and attached to the top section 112 as bestshown in FIG. 5, the engager 142 extends above the plane of the topsurface of the top section 112 and the engager 144 extends below theplane defined by the bottom surface of the top section 112. Theconductive plugs are thus sized and shaped to produce reliableelectrical continuity between the side frame and the bearing adapterwhen the bearing adapter pad 100 and the bearing adapter 50 arepositioned in the side frame pedestal opening.

In this illustrated embodiment, the conductive plug 130 and specificallythe central portion 140 include an outwardly extending mounting flangeor lip 148. The mounting flange 148 facilitates the attachment, formingcoupling, or mating of the conductive plug to the top section 112 of thebody 102 of the bearing adapter pad 100. In an alternative embodiment,the structure could be reversed such that the conductive plug includesone or more attachment slots or mounting slots sized to receive amounting flange formed or extending from the central portion of the bodyof the bearing adapter pad into the mounting slot(s). The mountingflange 148 facilitates a secure and fixed mechanical engagement betweenthe conductive plug 130 and the top section 112 of the body 102 of thebearing adapter pad 100. The present disclosure contemplates that theconductive plug may have more than one flanges or lips and that othersuitable mechanical connections may be employed to better engage the topsection of the body of the bearing adapter pad.

In this illustrated embodiment, the central portion of the conductiveplug also defines an inner aperture 150 which extends transverselythrough the central portion. This aperture 150 is sized to receive a pinor support in the mold which maintains the relative position of theconductive plugs during the molding of the load-bearing portion and therest of the bearing adapter pad 50 around the conductive plugs. Theaperture also facilitates spring action of the conductive plugs.Specifically, if the conductive plug is compressed or deformed, thematerial of the plug will tend to move or stretch into the space of theaperture. This, in part, allows for the spring-like action of theconductive plugs.

In various embodiments of the present disclosure, the conductive plugsof the bearing adapter pad of the present disclosure are made from aurethane to resist cold flow and to be sufficiently compressible orresilient. In various embodiments of the present disclosure, theconductive plugs include conductive particles such as carbon blackparticles which make these plugs conductive. In various embodiments ofthe present disclosure, the urethane conductive plugs are unfilledexcept with the conductive particles because urethane has a greatermemory characteristic which provides sufficient resiliency to the plugsand enables them to function in a spring-like manner. This issubstantially different than the previous known copper plugs which tendto break or crush because they have no relative resiliency. In variousembodiments of the present disclosure, the conductive plugs areinjection molded. It should be appreciated that the conductive plugscould alternatively be partially filled with strengthening material suchas glass particles or strands to add a desired amount of strength to theplugs; however, such additional strength would reduce the memory effectof the compressible resilient conductive plugs.

In various embodiments of the present disclosure, the conductive plugsare made from a urethane filled with approximately 20% to 25% of carbonblack particles. This material is commercially available from numeroussources such as RTP, Advance Polymer Compounding (APC), Noveon, Bayer,GE Plastics, and Dow Chemical. It should be appreciated that theconductive plugs can be made from a carbon black filled urethane in therange of approximately 10% to 50%, and that other ranges are possible.The plugs with the carbon black conductive particles serve to assureelectrical conductivity between the upper and lower surfaces of theconductive plug to electrically connect the side frame with the bearingadapter which in turn provides the car body with a grounding mechanismto avoid the build-up of static electricity in the car body and toprovide the ability to receive signals from the railroad tracks.

In one embodiment, the top section and legs of the bearing adapter pad100 are formed from a cast or injection molded polymer or elastomer suchas a cast elastomer of a durometer hardness between 90A and 58D. In oneembodiment, the top section and legs of the bearing adapter pad of thepresent disclosure are made by injection molding or otherwise suitablyforming the conductive plugs and then injection molding the top sectionand legs around and between the conductive plugs. More specifically, theconductive plugs can be injection molded cylindrical plugs placed in aninjection mold in a spaced-apart symmetrical relation and the topsection is injection molded around the conductive plugs under suitablepressure and heat to form the bearing adapter pad as a monolithicstructure. The top section and the conductive plugs are thus fusedtogether to form a one-piece bearing adapter pad. The flange or lip orother mounting member also provides a mechanical lock, engagement orcoupling between the conductive plugs and the top section of the bearingadapter pad.

In another embodiment, the top section and legs of the bearing adapterpad are formed from a cast or injection molded polymer or elastomer andthe plugs are press fit into the top section of the bearing adapter pad.In one such embodiment, the plugs do not include the mounting flanges,the top section is formed without the plugs, holes are drilled orpunched in the top section, and the plugs are press fit into the holes.

It should be appreciated that the present disclosure relates to: (a) thebearing adapter pad by itself; (b) the bearing adapter pad incombination with a bearing adapter; (c) the bearing adapter pad incombination with a bearing adapter and a side frame; (d) the bearingadapter pad in combination with a side frame; (d) the bearing adapterpad in combination with a bearing adapter and a side frame; (e) arailroad car truck including the bearing adapter pad among the othercomponents; and (f) a railroad car including the bearing adapter padamong the other components.

It will be understood that modifications and variations may be effectedwithout departing from the scope of the novel concepts of the presentinvention, and it is understood that this application is to be limitedonly by the scope of the claims.

1. An railroad car bearing adapter pad comprising: a body including atop section having a top surface and a bottom surface; a plurality oflegs extending from the body; and a plurality of spaced apartcompressible resilient conductive plugs positioned in the top section ofthe body, each of the conductive plug having a top engager that extendsslightly above the top surface of the top section and a bottom engagerthat extends slightly below the bottom surface of the top section tofacilitate electric conductivity or continuity between a side frame anda bearing adapter.
 2. The railroad bearing adapter pad of claim 1,wherein the conductive plugs are made from a resilient wear resistantmaterial which enables them to continue to provide electric conductivityor continuity even when they are compressed or deformed.
 3. The railroadbearing adapter pad of claim 1, wherein each conductive plug includes anoutwardly extending flange.
 4. The railroad bearing adapter pad of claim1, wherein each conductive plug includes a cylindrical portion.
 5. Therailroad bearing adapter pad of claim 1, wherein the plurality of spacedapart conductive plugs are symmetrically arranged in the top section. 6.The railroad bearing adapter pad of claim 1, wherein each conductiveplug defines a central opening.
 7. The railroad bearing adapter pad ofclaim 1, wherein each conductive plug is press fit into the top sectionof the body.